Improvement in steam-generators



tatea Mgg? Wm anni @time CHARLES VVHITTIER, OF BOSTON, MASSACHUSETTS, ASSIGNO TO HIMSELF AND BENJAIVIIN F. CAMPBEIJL, OF SAME PLACE.

The Schedule referre to in these Letters Patent and making part of the same.

To all whom 'it 'may concern Be it known that I, CHARLEs WHITTLER, of the city ofv Boston, in the State of Massachusetts, have invented certain new and useful Improvements in. Steam-Generators; and do `hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the iigures and letters marked thereon.

Of these drawings- Figure l is a side elevation of the exterior shell of the generator;

Figure 2 is a side elevation ofthe interior shell thereof;

Figure 3 is a longitudinal vertical section ofthe whole generator; and

Figure l:Lisa vertical cross-section thereof, taken in the line x x of iig. 3.

Similar letters of reference indicate corresponding parts in the several iigures.

The object of my improvements is to provide a generator for steam and water-heating purposes that will contain an increased heating-surface; that will more eff'ectually utilize the products of combustion; and that will not permit ofthe escape, ii'oln the metallic surfaces into the surrounding atmosphere, of unhealthy gases. Previous to my invention the products of combustion in horizontal boilers passed from front to back through round tubes, placed immediately, or nearly so, in the rear ofthe fire-bornand then into the smoke-due, carrying with4 them a large portion of caloric; or else the products passed from i'ront to back, and then returned through ues to the front,such luesbeing placed wholly within the water-space, at or near the base of the generator, and then into the smoke-flue. Not only heat was thus lost, but the heating-suriace was limited.

The general features of my invention consist in the construction of the ports, so that a good high combustion-chamber is obtained, the products of combustion passing about the tubes placed below the inner crown-sheet, the whole length of the generator, and at the same time along over the horizontal portion of a bridge-piece placed within the generator, at the back of the fire-box and ash-pit, until they are deflected down from the back end ofthe tubes, round underneath the lower horizontal siu'face of this bridge-piece, and then down the vertical surface contiguous thereto to the smoke-Hue. Also, by making the generator of two shells so connected with each other, the watertubes, and this bridge-piece, that there will be a free circulation of water and steam through thesejportions, resulting in the whole generator.

rIhis construction serves not only to increase the heating-surface, but aids to prevent the escape of gases through any part of the generators, except that they pass intp the water and steam-chamben'where they at once become neutralized, thus rendering the combustion oi' anthracite coal free ofthe danger of its throwing oft' into the extemal atmosphere, in connection with caloric (which is frequently utilized for hot-air pipes, by surrounding the generator with a brick casing,) gases deledeleterious to health.

In the drawings, c represents the exterior shell ofthe generator, composed ofwrought-iron, and having in one of its ends the tire and ash-door openings; l, the interior shell, composed ofthe same material, and being a counterpart ofthe exterior one, excepting that it is made smaller so as to form a water andV steam-chamber between the two, of a convenient and proper size, thus permitting ai'ree circulation oiwater and steam, about every portion ofthe generator, and around the iire and ash-doors and smoke-flue, as seen at c c c, Snc. These two shells are riveted or otherwise conveniently attached together at their base, and to casiugsplaced around the lire-chamber, ash-pit, and smoke-fine openings. Y

Immediately at the rear of the fire-chamber and ashpit, and forming the back thereof, is placed a bridgepiece ll, composed of cast-iron; this bridge-piece extends -up to the top of the tire-chamber, and then tinns back in a horizontalposition, or slightly depressed iiom such position, and runs back nearly to the` rear ofthe inner shell, b. This bridge-piece lies wholly Within the inner shell, but has periorations, or openings, in the inner shell, as shown at c e, Sac., so as to permit of the free circulation of the water, from the water-chamber formed by the two shells c and b, through it. The casting composing this bridge-piece is, at its edges, properly riveted on to the inner shell, and is, of course, steam-tight at its edges.

W'ithiu the combustion-chamber, just below the crown-sheet, is a number of round tubes, f j, Sto., properlyinserted into ithe interior shell, and running from front to back thereof, so as to permit of the free circulation or water and steam through them, from the water and steam-chambers, and the i'ree passage, out-r side, and between, and around them, belowthe crownsheet, ofthe products of combustion.

The tubes are preferred, as before stated, to be inclined or depressed from front to back.

g is the smoke-flue, which passes through both shells a and b, and takes the products of combustion out from under and around the bridgeypiece, after they have freely circulated about the same and the tubes f f, &c. h is the pipe which conducts the steam'o into the radiators, placed in desired parts of the building, though I prefer to take the steam from the generators at a point nearer the back part, as it is there drier. Water is taken into the chamber of the generator at any proper and convenient point.

I give the tubes a slight incline or depressed position, from ont to back, so that theywill leave a good high. combustion-chamber, and approach quite n ear the bridge-piece at the rear end. The horizontal portion of the brdge-piece can be made to incline,'so that it Will be parallel with these tubes, as shown in the drawings.

The utility of this arrangement is evident from the fact that, as the water passes up through the rear ends of the tubes f f, Svc., it is commenced to be converted into steam, and When it reaches the f iont end, it passes more quickly and rapidly into the steam-chamber.

The products of combustion are more eiective at this point, where steam is required to be made more quickly, and from here they pass along down and around the tubes, towards the back part, losing their greater effectiveness at a pointwhere the generation of steam is least required, but still where it is necessary to have the pipes in as close and efficient contact Withfthem as possible.

Claims 

